Correspondence between Nicholas Murray Butler, president of Columbia University from 1902 to 1945 and high level University administrators. Butler was one of the most influential figures at the University from the 1890s throughout the first half of the 20th century -- a critical period of development for the University. Prior to his appointment as president, Butler served as dean of the Faculty of Philosophy. Following his retirement in 1945 he continued to serve as president emeritus and a trustee of the University. As dean of the Faculty of Philosophy during the administration of President Seth Low (1890-1901), Butler was a major force behind the transformation of Columbia College into a University. As president, Butler led the University during one of its greatest periods of growth and change. Butler was intimately involved in numerous details of developing and administering the institution. The correspondence relates to a wide range of subjects involving the development, mission, organization, administration, facilities, finances, faculty, and student body of the University. However, the materials are not a comprehensive record of Butler's presidency. His administration can be understood more fully by also reading the correspondence of the trustees, deans, and other top administrators who held office during Butler's presidency.